The present invention relates generally to containers. More particularly, the present patent discloses and protects a method and device for use relative to a product container, such as a beverage or comestible container, that provides a thermochromic indication of a temperature of a volume of product that is retained within an open inner volume of the product container and increases the effective display surface of the product container by exploiting a single surface region to display a plurality of designs.
One knowledgeable in the art of containers, particularly beverage and comestible containers, will be well aware that a plurality of methods and devices have been disclosed for providing an indication of a temperature condition of a volume of material, typically liquid, that is retained within an open inner volume of the container. Of course, these methods and devices are intended to apprise a prospective consumer of the approximate or exact temperature condition of the retained liquid so that the user can rely and act thereon. For example, certain of these inventions can indicate to a user the overall temperature condition of a retained liquid, such as hot or cold. With this, for example, a user simply desiring a cold liquid can ensure that the liquid is cold and a user simply desiring a hot liquid can ensure that the liquid is hot. Other types of temperature indicating devices have been disclosed for providing a more exacting indication of temperature, such as an exact temperature of the retained liquid or in which temperature range of a plurality of small (i.e., 2-5 degree) temperature ranges the retained liquid resides.
Many of these prior art devices employ thermochromic liquid crystal mesophase material, which as its name suggests exhibits a change in color in response to a change in temperature. Stated more particularly, thermochromic liquid crystal mesophase materials have predetermined active temperature ranges in which they change color to indicate that they are in that predetermined active temperature range. Since the active temperature range of thermochromic liquid crystal material can be calibrated to suit particular requirements or desires, temperature indicating devices have been created with selected xe2x80x9chotxe2x80x9d and xe2x80x9ccoldxe2x80x9d temperature ranges or selected individual temperature ranges.
Thermochromic liquid crystal mesophase materials technically pass through all colors of the visible spectrum in sequence as the material""s temperature is varied through its predetermined active temperature range. However, three colors typically predominate: a brownish-red color will be followed by a green color that leads to a blue color. Outside its active temperature range in either direction, standard liquid crystal mesophase material appears as black against a black background. Exploiting this, prior art devices have interposed black numeric characters representative of the material""s active temperature range between a transparent protective layer and the liquid crystal material. With this, the numeric characters will become apparent only when the liquid crystal material is in its active temperature range.
Employing this technique, devices of the prior art have created strips with a plurality of sequentially calibrated thermochromic liquid crystal events, each with a respective numeric temperature indication. These strips have been adhered to the external surfaces of containers, such as beverage containers, by adhesive or the like. With this, the heat condition of a volume of liquid retained in the container will be conducted to the strip of thermochromic liquid crystal events. This, in turn, will cause the liquid crystal event corresponding to the temperature of the contained liquid to enter its active temperature range thereby revealing the otherwise obscured numeric characters. With this, the temperature of the contained liquid will be depicted.
These prior art devices certainly have provided useful contributions to the present state of the art. However, they do typically suffer from a number of disadvantages. For example, by occupying a sizable portion of the surface are of the beverage container, they necessarily detract from the surface area available for advertising, relaying product background information, and similar purposes. Furthermore, devices of the prior art typically have merely relayed the general or particular temperature condition of a retained liquid without improving the appearance and advertising characteristics of the container. Indeed, the utilitarian nature of prior art temperature indicating devices have commonly detracted from the aesthetics of the beverage container relative to which they are employed. Still further, since many prior art devices have been designed to be affixed to a beverage or other product container after its construction, it is likely that application of the devices to the surface area of the container would obscure advertising or product information on the actual surface of the container.
In light of the foregoing, one will appreciate that, notwithstanding the plurality of temperature indicating devices that have been disclosed by the prior art, there remains a need for a thermochromic device for use relative to a product container that exploits thermochromic materials not only to exploit fully the available surface area of the product container but actually to increase the effectively available surface area of the container without requiring a concomitant increase in the actual surface area.
Advantageously, the present invention is founded on the basic object of providing a thermochromic device and method for use with a product container, such as a can or the like, that incorporates thermochromic material to increase the effective surface area of the product container with which the device is used.
An underlying object of the invention is to provide a thermochromic device and method that allows the display of a plurality of different temperature-dependent images on a single surface region of the product container. Stated alternatively, the present invention sets about providing, for example, a thermochromic device and method that is capable of displaying a plurality of images on a single surface region, each over an ideally unique temperature range.
A further object of the invention is to provide such a device and method that can be formed integrally with a product container or fixedly or removably coupled thereto.
Yet another object of the invention is to enhance the safety of users of certain product containers by apprising the user of the temperature condition of the retained product.
A related object of the invention is to provide a thermochromic device and method that adds to a user""s overall enjoyment of a retained product by indicating to the user whether the retained product is in a desired temperature condition.
In certain embodiments of the thermochromic device and method, a further object of the invention is to provide an indication of the temperature condition of a retained product on a cap, lid, or other upper surface of a product container whereby consumers of potentially hot liquids or comestibles, such as coffee, tea, or soup, will be made aware of whether the liquid or comestible is in a dangerously hot condition, an ideal temperature condition for consumption, or an unsatisfactorily cold condition.
A still further object of certain embodiments of the invention is to provide thermochromic indications of the temperature condition of a retained product not only on a side surface of a product container but also on an upper surface of the product container.
Of course, additional objects and advantages of the present invention will be obvious both to one who reads this specification and reviews the accompanying drawings and to one who has an opportunity to make use of an embodiment of the invention.
In accomplishing the aforementioned objects, a most basic embodiment of the invention comprises a thermochromic device and method for use relative to product containers that provides thermochromic indication of a temperature of a volume of product that is retained within an open inner volume of the container while increasing the effective display surface of the container by exploiting a single surface region to display a plurality of designs. The thermochromic device and method essentially comprises a substrate layer with an image display region, a first image display overlying the image display region of the substrate layer, and a second image display overlapping with the first image display and overlying the image display region of the substrate layer. At least one of the first and second image displays under the invention comprises a thermochromic image display with an active temperature range over which the thermochromic image display becomes apparent.
With this, where the first image display is non-thermochromic, the thermochromic device, and thus a product container to which it is applied, will display the first image display when the thermochromic device is outside the active temperature range of the second, thermochromic image display. The thermochromic device, and thus the product container in general, will display the second image display when the thermochromic device is within the second image display""s active temperature range.
When the thermochromic second image display becomes visible and active by entering its active temperature range, it could entirely obscure the first image display. Alternatively, upon becoming active and visible, the thermochromic second image display could interact with the first image display to supplement or modify the first image display. It is also within the scope of the invention for there to be third or further image displays, which also can be thermochromic. A third image display could have an active temperature range that overlaps the active temperature range of the second, and possibly other, thermochromic image displays. Alternatively, the active temperature range of the third image display could be entirely disparate from the active temperature range of all other thermochromic image displays. The third image display could entirely obscure the first and second image displays, or it could modify or supplement one or both other image displays. In any case, the active temperature ranges for the thermochromic image displays could be calibrated to cause the thermochromic image displays to become active over a given temperature range below a selected temperature or over a given temperature range in excess of a selected temperature.
The substrate layer to which the image displays are applied could comprise a layer of sheet material that could be affixed to a surface of a product container. For example, the substrate layer could comprise a sheet of paper material or a sheet of plastic or MYLAR material. Where a layer of sheet material is employed, an adhesive backing may be applied to a first surface thereof for affixing the layer of sheet material to a product container and the image displays may be applied to the second, opposite surface of the layer of sheet material. By way of reference, one may note that MYLAR material is available from the Minnesota Mining and Manufacturing Company (xe2x80x9c3M Companyxe2x80x9d) of St. Paul, Minn. In lieu of adhesive, the sheet material could be retained on the product container by being tightly wound therearound. Alternatively, the substrate layer could comprise the actual surface of the material container whereby the image displays would be applied directly thereon.
In certain embodiments, a thermochromic device can be applied most uniquely to an upper surface of a container. Again, the container could be a beverage container for retaining a beverage product. However, it must be clear that the container could just as well retain any type of comestible product including soup and the like. With this, a prospective consumer could be informed of the temperature condition of the retained product without a need for lifting the container. With this, determining the product""s temperature condition certainly would be more convenient. Furthermore, the possibility of unnecessarily tilting or spilling the product would be eliminated. In certain still more unique embodiments, the thermochromic device at the upper surface of the container could be supplemented by a thermochromic device applied to a side surface of the container. With this, a user could discern the temperature condition of a retained product both from a side view and from a top view.
Relative to can-type containers, such as a typical beverage container, a thermochromic device applied to the upper surface of the container can be fixed to or directly applied to the metallic can top. Also, since beverages served in cans typically are ideally served cold, the thermochromic device in such cases will likely enter its active temperature range well below room temperature. For example, the device may be calibrated to enter its active temperature range below 45 degrees Fahrenheit.
One will appreciate, however, that the present invention could also be embodied still more uniquely and to great advantage in a removable lid of, for example, a coffee cup, a soup bowl, or any other lidded product container. There, the thermochromic device would allow a user to determine the temperature condition of the retained product conveniently and, in doing so, would also prevent the consumer from being scalded or having his or her tongue burned by searingly hot coffee or the like.
The astute observer may appreciate that, where the thermochromic device of the present invention is employed relative to the upper surface of a container, be it in a can top or in a removable lid or cap, the thermochromic device may not function accurately if consistent or constant contact is not maintained between the product and the surface to which the thermochromic material is applied. The inventor has discovered that this could be accommodated in at least two ways. One such way is to calibrate the thermochromic material to account for the lack of contact between the product and the container surface and to provide a temperature indication based on the heat transfer principles of convection and conduction from the product, to the air, to the lid or cap, and to the thermochromic device.
However, a more reliable and likely more accurate method devised by the inventor is to provide or create a depression in the lid, cap, or other upper surface of the container wherein the depression has a base that is calculated to dip into the volume of product. The thermochromic material or device could then be applied to the base of the depression whereby, assuming a sufficiently full container, constant contact between the product and the surface to which the thermochromic material is attached would be maintained. With this, the thermochromic device would be accurate in function but would be simple in structure and theory.
The image displays can certainly be formed in any one of a number of ways that would occur to one skilled in the art. For example, non-thermochromic images can be formed with any one of a variety of readily available materials including paints, inks, films, and decals. U.S. Pat. No. 5,265,532, which is incorporated herein by reference, provides a detailed description of an apparatus and method for decorating cylindrical containers. The thermochromic image displays can be formed from a variety of thermochromic materials including thermochromic liquid crystal material and thermochromic ink. One knowledgeable in the art will appreciate that typical thermochromic inks are founded on the combination of an electron-donating color forming material and an electron-accepting color developing material. Further background may be had to U.S. Pat. Nos. 4,028,118 and 4,732,810, which are incorporated herein by reference. In any case, one skilled in the art will be aware that any one of a variety of methods, such as painting, coating, spraying, dipping, marking, screen printing, offset printing, and gravure printing, will allow the plurality of image displays to be printed in an overlapping manner. The preferred thermochromic materials will be color reversible whereby the created device could be used repeatedly where appropriate.
By employing such materials, the thermochromic display images can be formed to demonstrate reversible color changes to red, purple, yellow, blue, green, orange, and a variety of intermediate colors. With this, substantially any desired display image can be created. For example, display images can provide advertising messages that become visible when the product container enters the thermochromic material""s predetermined active temperature range. Alternatively, the display images can apprise a prospective consumer of the temperature condition of the retained product. Still other uses for the multiple thermochromic images will be obvious to one skilled in the art after reading this disclosure.
With a plurality of embodiments of the present invention for a modular wall component generally described, one will appreciate that the foregoing discussion broadly outlines the more important features of the invention merely to enable a better understanding of the detailed description that follows and to instill a better appreciation of the inventor""s contribution to the art. Before any particular embodiment of the invention is explained in detail, it must be made clear that the following details of construction, descriptions of geometry, and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention.